Coating material



Patented Dec. 27, 1932 UNITE) ST EDWARD F. JOHNSTON, F WILMINGTON, DELAWARE COATING MATERIAL No Drawing.

The resent invention relates to water 1 proof s eets characterized by transparency and a high degree of flexibility.

Primarily the invention contemplates a wrapping material in the form of a sheet or fabric comprising a thin gelatin or cellulose base and a water proof coating applied thereto.

An object of the invention, moreover, is to provide a method of printing upon sheets or fabrics of the present invention and applying the water proof solution in such manner that the effect would be thoroughly protected.

An additional embodiment of the invention contemplates incorporation of a substance in the sheet which will impart a pleasant aroma thereto as well as the incorporation of antiseptic materials and tinting or coloring material.

In carrying out the invention, I use as a base any one of a number of commercial varieties of transparent sheets and fabrics.

There are, of course, numerous sheets formed of cellulose derivatives, synthetic resins, and the like, but I prefer to use as the core or base transparent gelatine because I find the latter, when provided with a coating in accordance with this invention, imparts a cushion like effect and likewise possesses the attributes of flexibility and is not so subject to wrinkling or cracking as with other types of bases.

The principal ingredient of the coating solution will comprise a cellulose derivative of which cellulose esters such as cellulose acetate are examples, but I prefer to use cellulose nitrate.

While cellulose nitrates with various degrees of viscosity may be satisfactorily em- 40 ployed, the coating solution is preferably formed b the use of high viscosity nitrocellulose. desire nitrocellulose of high viscosity for two reasons, namely, because less of the nitrocellulose will be required, and the i resulting film or coating has an excellent tensile strength.

In referring to high viscosity cellulose, I mean cellulose having viscosity above substantially fifteen seconds.

In addition to the cellulose derivative,

Application filed April 10, 1931.

:Linseed oil Serial No. 529,805.

preferably nitrocellulose of high viscosity, the solution also comprises one or more ums such as damars, kauri, ester, and copal. ther gums of this general type may be utilized there being, of course, innumerable commercial varietles. I prefer copal on account of its hardness and miscibility with high viscosity nitrocellulose.

I also employ as another component of the solution one or more of a number of plasticizers such as dibutyl phthalate, camphor, castor oil, linseed oil, "and oxygenated derivatives of the turpenes. I prefer to employ castor oil alone or castor oil in combination with a dr ing oil such as linseed oil on account of its cheapness, its ease of handling and its quality of retaining plasticity.

I preferably employ a solvent such as amyl, .butyl, or ethyl acetate, and one or more diluents of the general character of gasoline, toluol and ethyl alcohol. With respect to the solvents and diluents, it will be. recognized that there is a wide range of equivalents, any of which I find satisfactory in forming the present solution.

In order that the composition of the coating solution forming a part of this invention may be readily understood, I furnish below two representative examples p I Formula #1 Denatured alcohol 4000 cc. Gasoline 6000 cc. High viscosity cotton... 1500 grams Amyl acetate 10000 cc. Castor oil 1075 cc. Linseed oil- 1075 cc.

Formula #2 Denatured alcohol 3000 cc. Toluol 1000 cc. Gasoline 4000 cc. High viscosity cotton 1500 grams Ethyl acetate 6000 cc. Butyl acetate 4000 cc. Copal gum solution 1182 cc. Gastor oil 1075 cc.

Formula #3 Amyl acetate 10000 cc. Acetic acid 50 cc. Castor oil 100 cc. High viscosity cotton; 1500 grams Of course, the specific quantities given may be departed from as well as the particular components and I have simply given these examples as two explanatory compositions.-

In Formula #3, the idea of using straight amyl acetate is to effect a strong clear film. The castor oil is used as a plastic and the ace- -tic acid softens the gelatin under-coating and Denatured alcohol 2% gallons Gasoline 2 gallons Gum 8% pounds It will be observed that all of the formulae set forth provide a finishing layer or coating which is devoid of waxes or other materials which require high heat for their application as has been customary in the prior art. Furthemore, such a wax-free layer is relatively adhesive and the combination thereof with the base is more intimate and complete than in the case of wax and stearate containing compositions.

carrying out the invention, a sheet of transparent gelatin or other fabric is completely coated with a thin film of the cellulose solution herein described which may be applied either with a brush, with a spray gun, or by passing the sheet or fabric through a bath of cellulose solution in which latter method the sheet will usually be passed between doctor blades so that any excess solution is scraped away and an even sheet both as to surface and thickness is the result.

As heretofore stated, the sheet of the pres ent invention is capable of being impressed or printed upon and the printing, photoengraving, photogravuring, lithographing, or the transfers of the decalcomanias, is preferably done upon the gelatin sheet before the sheet is coated with a water proofing cellulose solution. By this process, the impressing or imprinting is protected.

The water proofing solution described herema also compriseas a component various substances which will impart an aroma or perfume to the finished product, as for instance, cedar oil, essential oils, odors of varioiu's' flowers, camphor odor, and in addition, may also contain an antiseptic material of which there are a large number of commercial varieties. I mention cedar oil "because this oil has the property of being beneficial in the wrapping of cigars and tobacco, but any odor taken up by alcohols, solvents or oils may be employed and preferably one having a beneficial effect upon the goods contained in the Wrapper.

The base or core will, in the usual manufacture of wrapping materials be provided with coating upon both of its surfaces, but it will be understood that a coating on one surface will at times meet requirements.

Furthermore, it will be appreciated that while I have described my coating particularly for use with thin flexible sheets such as gelatin, that it may be employed with equal effect upon other materials and for other purposes.

' Color mediums may be em loyed in making colored sheets either by using dyed nitrocellulose in the solutions instead of undyed nitrocellulose or the color will be introduced into the solution in the form of a dye preferably a spirit soluble dye.

The transparent waterproof sheet can be printed and used for advertising purposes, and can be colored and used for colored light purposes. It can be made thick enough to be used for lamp shades and any number of other uses.

Modifications of the invention may, of

course, be resorted to, all of which are considered as comprehended within the scope of the appended claims.

1. A freely flexible and transparent ink printed sheetvwrapping material comprising a substantially transparent base having an ink imprint thereon, and a transparent waterproof layer over said printing having as a principal ingredient a high viscosity cellulose derivative selected from a group consisting of high viscosity nitro-cellulose and high viscosity cellulose acetate, and containing an oil, a gum, and a base softening agent.

2. The method of producing highly flexible and transparent printed sheet wrapping material which comprises providing a transparent base, ink printing on said base and thereafter coating the printed surface with a transparent layer having as a principal ingredient a high viscosity cellulose derivative selected from a grou consisting of high viscosity nitro-cellulose and high viscosity cellulose acetate, and containing an oil, a gum and a base softening agent.

3. A freely flexible and transparent ink printed sheet wrapping material comprising a substantially transparent gelatin base having an ink imprint thereon, and a transparent waterproof layer over said printing having as a principal ingredient a high viscosity cellulose derivative selected from a group consisting of high viscosity nitro-cellulose and high viscosity cellulose acetate, and containing an oil, a gum, and a base softening agent. 4. A highly flexible and transparent sheet wrapping material comprising a substantially transparent base and a transparent Waterproof layer over said base having as a principal ingredient a high viscosity cellulose derivative selected from a group consisting of high viscosity cellulose acetate and high viscosity cellulose nitrate and containing an oil and a gum and a base softening agent. 5. A highly flexible and transparent sheet wrapping material comprising a substantial- 1y transparent gelatin base and a transparent waterproof layer over said base having as a principal ingredient a high viscosity cellulose derivative selected from a group consisting of high viscosity cellulose acetate and high viscosity cellulose nitrate and containing an oil and a gum and a base softening agent.

In testimony whereof I have hereunto set my hand.

EDWARD F. JOHNSTON. 25. 

